During the motion of transportation facilities, shock vibration can be most detrimental. For example, such shock vibration can cause damage to the mechanical structure of the vehicles concerned, such as to shorten or diminish their service life and even to cause damage.
It should be understood that towing of combination vehicles means a combination of vehicles, linked one to the other, such that at least one is being towed by another. Previously, one-way buffer arrangements have been known but these cannot be satisfactorily used in towing combinations. Accordingly, the problem of alternative two way shock vibration along an axis of towing combination vehicles has not been solved simply and reliably until this invention. Such one-way buffers, therefore, cannot be reliably used in the towing means for a train, mine-haul truck, common truck, etc. In particular, the one-way buffer only provides a time lag for starting, which is necessary in the starting process of towing combination vehicles, but it cannot eliminate the great inverse shock caused by braking, especially emergency braking, and moving down along a slope, which seriously affects the service life and safety of transportation facilities.
It is well known that because only one-way shock proof buffers are available, which is effective when starting, is for example provided between railway carriages, great inverse shock will be caused to the railway carriages by slight braking during motion, and by the combination of great shocks between railway carriages, as may be caused by emergency braking or bumping of trains and in other situations will result in turning carriages over and in injuries and deaths of passengers. Such serious accidents have repeatedly occurred in transportation throughout the world.
The application of a two-way shock proof and shock absorbing towing coupling prevents the carriages from being turned over when bumping, even in serious accidents, so as to decrease injuries and deaths, and may eliminate shock vibration which results from braking and running, so as to ensure smooth and steady motion, and increase service life of trains.
Combination vehicles for highway transportation is an ideal way of transportation. However, if a one-way buffer is still used as the towing coupling of the combination vehicles, such combination vehicles can't normally be used because of the inverse shock of the towed vehicles on the leading vehicle and the bumping between the towed vehicles. Therefore, the key reason that there have not been combination vehicles used as real transportation tools for highway transportation so far is that the technique of two-way shock proof and shock absorbing towing coupling has not been provided.
In the towing of marine vehicles or boats, rope connection has long been used. Some factors, such as wind and wave variation, together with the variation of ship speed, result in speed differences and frequent two-way shock between the towing vehicle and the vehicle being towed. The shock stress can be very great, although some shock proof means, such as palm fiber packages, used tires, and the like, are provided on ends of towboats. In order to decrease or avoid the bumping between the marine craft, the distance between such crafts can be enlarged. Thus, towing efficiency is decreased, and energy is wasted. Therefore, two-way shock proof connection is also a key problem to be solved pressingly in water towing transportation.
When a boat anchors, a general method is to tie it to piles by ropes. For a large marine craft such as a big ship, complex facilities, such as the winch and steel cable, and heavy labor operations are often necessary. Because of the great inertia, and because of the long and large ship body and shake of the ship, the ship often bumps the wharf violently. Although some shock proof means, such as hanging pads made of bundles of rubber belts are used, the great bumping stress still results in the deformation of the ship body on both sides. Therefore, one of the difficult technical problems which needs to be solved urgently for anchoring of ships and boats is how to solve thoroughly the two-way shock which may cause disconnection and how to simplify the facilities for anchoring.
To sum up, once two-way shock proof and shock absorbing for towing transportation of various combination vehicles is solved, efficiency and benefit of transportation and service life and safety of transportation facilities will be increased greatly.